Alternate spelling (or maybe the guys at TSG just don't know how to spell) for the word conk. It refers to a means of straightening frizzy hair, or the resulting hairstyle subsequent to such straightening.

We found this one in the FBI file of Jack Lord, the late star of Hawaii Five-0 and the only white guy to wear a konk. -- From The Smoking Gun Archive.

A Korean. Also known as a spoon-face or shovel-head.
Derived from the Japanese word "Kankokujin" (pronounced Kahn-koe-koo-jin) , meaning "Korean". Typically used as an insulting slur to reffer to a korean person. Unlike other racial slurs like "nigger", koreans are for the most part unaware of the meaning of this word and will thus not take offense when it is mentioned in front of them.

Korean: *Yells something in korean at john, then turns to his korean friends and bursts out laughing*